Air carrier pilot concerned with ZLC frequency congestion when operating in wyoming area airports.

Attributes
ACN	521546
Time
Date	200108
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zlc.artcc
State Reference	UT
Altitude	msl single value : 15000
Aircraft 1
Controlling Facilities	artcc : zlc.artcc artcc : zbw.artcc
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time type : 2347
ASRS Report	521546
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took precautionary avoidance action other
Consequence	other
Supplementary
Problem Areas	FAA Flight Crew Human Performance Environmental Factor ATC Human Performance Airspace Structure

Narrative:

Excessive frequency saturation: all of northwest wyoming is working just one ATC sector and common high, low altitude, and local frequency of 133.25. As a consequence, all users are trying to transmit and receive on same frequency at same time. Virtually every transmission is blocked by another transmission. Local aircraft on ground at northwest wyoming airports are calling for ATC clearance, not realizing they are blocking high altitude, slc xmissions due to terrain masking. The frequency congestion here is worse than any location on the east coast! Recommend slc center split the low/high altitude sectors with separate frequencys, and a 3RD frequency for aircraft on the ground to pick up their IFR clearances/void times. During high volume weekend times, the center has to repeat almost every transmission 3-4 times before the receiving aircraft will acknowledge it. This results in overloaded controllers and degraded ATC performance. We were 'left' on a sequencing vector twice on this flight, had to remind the controller for additional instructions. Slc then forgot to hand us off to the next sector 124.35. We finally switched ourselves to den center. Callback conversation with reporter revealed the following information: reporter alleges that the frequency congestion problem is markedly worse on the weekends, late morning through mid afternoon.

Original NASA ASRS Text

Title: ACR PLT CONCERNED WITH ZLC FREQ CONGESTION WHEN OPERATING IN WYOMING AREA ARPTS.

Narrative: EXCESSIVE FREQ SATURATION: ALL OF NW WYOMING IS WORKING JUST ONE ATC SECTOR AND COMMON HIGH, LOW ALT, AND LOCAL FREQ OF 133.25. AS A CONSEQUENCE, ALL USERS ARE TRYING TO TRANSMIT AND RECEIVE ON SAME FREQ AT SAME TIME. VIRTUALLY EVERY XMISSION IS BLOCKED BY ANOTHER XMISSION. LOCAL ACFT ON GND AT NW WYOMING ARPTS ARE CALLING FOR ATC CLRNC, NOT REALIZING THEY ARE BLOCKING HIGH ALT, SLC XMISSIONS DUE TO TERRAIN MASKING. THE FREQ CONGESTION HERE IS WORSE THAN ANY LOCATION ON THE EAST COAST! RECOMMEND SLC CENTER SPLIT THE LOW/HIGH ALT SECTORS WITH SEPARATE FREQS, AND A 3RD FREQ FOR ACFT ON THE GND TO PICK UP THEIR IFR CLEARANCES/VOID TIMES. DURING HIGH VOLUME WEEKEND TIMES, THE CENTER HAS TO REPEAT ALMOST EVERY XMISSION 3-4 TIMES BEFORE THE RECEIVING ACFT WILL ACKNOWLEDGE IT. THIS RESULTS IN OVERLOADED CTLRS AND DEGRADED ATC PERFORMANCE. WE WERE 'LEFT' ON A SEQUENCING VECTOR TWICE ON THIS FLT, HAD TO REMIND THE CTLR FOR ADDITIONAL INSTRUCTIONS. SLC THEN FORGOT TO HAND US OFF TO THE NEXT SECTOR 124.35. WE FINALLY SWITCHED OURSELVES TO DEN CTR. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ALLEGES THAT THE FREQ CONGESTION PROB IS MARKEDLY WORSE ON THE WEEKENDS, LATE MORNING THROUGH MID AFTERNOON.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.